Formation of pigment precursor (+)-1''-methylene-6''-hydroxy-2H-furan-5''-one-catechin isomers from (+)-catechin and a degradation product of ascorbic acid in a model wine system

J Agric Food Chem. 2009 Oct 28;57(20):9539-46. doi: 10.1021/jf902198e.


The present study investigates the contribution of ascorbic acid to the formation of pigment precursors in model white wine systems containing (+)-catechin as the oxidizable phenolic substrate. The two main colorless products in these systems were structurally characterized as isomers of (+)-catechin substituted at either C6 or C8 on the A ring with a furan-type unit, namely, (+)-1''-methylene-6''-hydroxy-2H-furan-5''-one-6-catechin and (+)-1''-methylene-6''-hydroxy-2H-furan-5''-one-8-catechin. A known degradation product of ascorbic acid, L-xylosone, was separately prepared and, when reacted with (+)-catechin, generated the same (+)-furanone-catechin isomers as in model white wine systems. Incubation of these isomers in wine-like conditions yielded yellow xanthylium cation pigments. This study has shown that undesirable spoilage reactions (yellow coloration) can occur from a breakdown product of ascorbic acid-L-xylosone.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascorbic Acid / chemistry*
  • Catechin / chemistry*
  • Isomerism
  • Models, Biological
  • Oxidation-Reduction
  • Pigments, Biological / chemistry*
  • Wine / analysis*


  • Pigments, Biological
  • Catechin
  • Ascorbic Acid